Field
Embodiments of the present invention relate generally to data storage systems. More particularly, embodiments of the invention relate to data communicated across a Fibre Channel network.
Background Information
In modern computer systems, a file system stores and organizes computer files to enable a user to efficiently locate and access requested files. File systems can utilize a storage device such as a hard disk drive to provide local access or provide access to data stored on a remote file server. A file system can also be characterized as a set of abstract data types that are implemented for the storage, hierarchical organization, manipulation, navigation, access, and retrieval of data. The file system software is responsible for organizing files and directories.
Many companies and individuals with large amounts of stored data employ a file system as a data storage system. These data storage systems can be located local to the data to be backed up or at a remote site. The data storage systems can be managed by the entity controlling the data storage devices or a data storage service company. Data can be added to the storage system at any frequency and at any amount.
Data storage systems may offer storage for backup and disaster recovery. Transfer to remote storage may require the transfer of data over a network. One network that allows transferring data across a data storage system is a Fibre Channel (FC) network. Fibre Channel allows a server and/or a storage unit to be located at a substantial distance from other components of the data storage system if optical fiber is used as the physical medium. However, optical fiber is not required for shorter distances, as a Fibre Channel network may also be implemented using coaxial cable and ordinary telephone twisted pair.
A storage area network (SAN) that communicatively couples independent systems in a data storage system can be implemented with Fibre Channel networking. Independent systems in an FC SAN network are colloquially known as “nodes,” which can be a client, a server, or a system that operates as both a client and a server.
In a typical distributed architecture, a node is communicatively coupled to a network with a host bus adapter (HBA). In an FC SAN network, the HBA of a node can be addressable through a World Wide Name (WWN). A WWN of an HBA can be, for example, a World Wide Node Name (WWNN), a World Wide Port Name (WWPN), or some combination thereof. A WWNN can identify a node in an FC SAN network and can be seen on many different ports of the node to identify the ports of the node as multiple network interfaces of that one node. In one example of an FC SAN network, a first node (e.g., a client) acts as a Small Computer System Interface (SCSI) initiator that issues SCSI requests to a SCSI target at a second node (e.g., a server) over an FC SAN network by addressing the second node using at least a WWNN assigned to one or more ports of an HBA at the second node.